A. The area is 4 square units
B. The description is below
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Break the figure into two parts along the dashed line. So we get a triangle on the left and a rectangle on the right.
The triangle has horizontal base of 3-1 = 2, and height 2. It's area is base*height/2 = 2*2/2 = 4/2 = 2 square units.
The rectangle is 1 by 2, so it's area is length*width = 1*2 = 2 square units.
Combine the two smaller areas to get the overall area: 2+2 = 4 square units
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As an alternative, you can use the trapezoid area formula
b1 = 3 and b2 = 1 are the two parallel bases
h = 2 is the height
A = area of trapezoid
A = h*(b1+b2)/2
A = 2*(3+1)/2
A = 2*4/2
A = 8/2
A = 4 square units
